THE PsELAPHID@ OF NorTH AMERICA. 37 
T. convExuLum, Lec. Deep yellow, very convex, more 
slender than the other species, pubescence not visible; body 
impunctate, highly polished: Length 0.7 mm. Plate XI., 
Fig. 94. 
_ Head nearly as wide as the prothorax, frontal margin arcu- 
ate between the antennz, width across the tempora one-fourth 
less; foveze and sulcus deep, the latter dilated in front; occi- 
put carinate. Avtenne, from the base of the first joint to that 
of the last, as long as the head, last joint about half as long, 
oval, three-fourths as thick as long, with short pubescence. 
Palpi with the last joint more oval, oblong. Prothorax long- 
er than wide, sides sinuate near the base, the transverse sulcus 
deep, slightly and very broadly angulated in the middle, lateral 
foveze none. AZ/ytra convex, bifoveate at the base, the ele- 
vations between them not so high as in dudzwm. Abdomen as 
in dubcum, but the first dorsal segment is much longer than 
the second, with two short basal carinz and lateral basal de- 
pressions as in atrisus. The fourth and fifth dorsals are 
connate, the contiguous limits scarcely discernible; ventrals 
correspond in length with the dorsals. Legs slender. Sexual 
differences of the clypeus as in dudbzum. 
Habitat. Illinois, Pennsylvania, Florida. 
This species answers better to the description of the genus 
Trimium than the others, if we assume as characteris- 
tic the length of the abdominal rings, while all the other 
species would coincide with Mr. Reitter’s genus 7rzmzopszs. 
Dr. Sharp considers Zyr¢mzum and Tyrimzopsis as hardly dif- 
ferent. 
T. pupium, Lec. Deep yellow, very convex, nearly circular 
in transverse section, no pubescence visible. Surface, except- 
ing the head, smooth and polished. Length,1.0oomm. Plate 
XI., Fig. 95. 
Head of the form of parvulum, except in the frontal margin 
being obtusely angulate; punctulate, no occipital impression; 
the foveze large but not deep, the sulcus fine in some speci- 
mens, deeper in others, and slightly foveolate next to the 
